|
Characteristics
|
Nanoemulsions
|
Microemulsions
|
| Definition |
Colloidal system of two immiscible liquids |
Swollen micelle |
| Order of mixing |
Only formed when surfactants are first mixed with oils |
Order of mixing does not matter |
| Thermodynamic stability |
Non-equilibrium |
Equilibrium |
| Kinetic stability |
Stable |
Less stable |
| Size |
<200 nm |
10-100 μm |
| Droplet size control |
Depend on surfactant/oil ratio |
Exhibit different phases with different nanosize morphology |
| Destabilization |
Ostwald ripening only |
Dilution and temperature change |
| Preparation |
High energy or low energy methods |
Spontaneous emulsification (depends upon temperature, composition, and pressure) |
| Characterization methods with dilution step |
Applicable |
Invalid as the droplet size increase |
| Dilution and temperature |
Robust |
Strongly affected |
